Category: Electronic Warfare

Grumman’s Model G-96, known as the TF-1Q (later designated EC-1A Trader), is a little known variant of the C-1 Trader carrier onboard delivery (COD) aircraft (which itself is a version of the ubiqitious S-2 Tracker carrierborne antisubmarine aircraft. The TF-1Q was the first dedicated electonic warfare (EW) training platform.

The first TF-1Q was delivered in 1957 to VAW-33 in San Diego. The TF-1Q carried a crew of 5 total, including 2 pilots and 3 ECM operators. The TF-1Q shared the same airframe as the C-1A Trader and therefore a volumoius fuselage in which to carry a wide variety of ECM (electronic countermeasure) equipment including:

The TF-1Q differed from the C-1 Trader in many ways. The compartive greater weight meant the TF-1Q did not operate from aircraft carriers. Also the TF-1Q was limited in range and altitude.

There were 4 total TF-1Qs. Provding bi-coastal EW training, coverage 2 TF-1Qs each were assigned to VAW-33 (later redesignated VAQ-33 “Firebirds”) then based at NAS Quonset Point, RI and the other 2 went to VAW-13 (later redesignated VAQ-130 “Zappers”) at then at NAS Alameda, CA. Additional tasking of these squadrons included providing EW “Red Air” for both east and west coast squadrons. These aircraft privided valuable realistic EW training for crews aboard ships.

As mentioned there were 4 TF-1Qs (listed bureau numbers follow):

136783: TF-1Q to EC-1A 1962. Was stored at Western International Aviation in Tuscon, AZ. Airframe scrapped.

136785: (fate unknown, probably scrapped.

136788: TF-1Q to EC-1A in 1962. She was converted back to C-1A Trader at some point. She was lost 2 April 1982 while on a COD flight from the USS Dwight D Eisenhower (CVN-69). All 11 aboard were killed.

13688: was FAA registered N788RR which was cancelled (and now belongs to a 2000 SOCATA SOCATA-TBM700) and reregisted as N6788 which expired June 2013.

The same techniques guided ancient Polynesians in the open Pacific and led Sir Ernest Shackleton to remote Antarctica, then oriented astronauts when the Apollo 12 was disabled by lightning, the techniques of celestial navigation.

A glimmer of the old lore has returned to the Naval Academy.

Officials reinstated brief lessons in celestial navigation this year, nearly two decades after the full class was determined outdated and cut from the curriculum.

That decision, in the late 1990s, made national news and caused a stir among the old guard of navigators.

Maritime nostalgia, however, isn’t behind the return.

Rather, it’s the escalating threat of cyber attacks that has led the Navy to dust off its tools to measure the angles of stars.

After all, you can’t hack a sextant.

I was in the “never should have quit” camp, btw. That’s the same position I take on paper maps and protractors for land navigation.

This 1940s sextant is among the supply stored at the Naval Academy. Midshipmen were tested on celestial navigation for more than a century before the required class was cut in the late 1990s. (By Tim Prudente / Capital Gazette)

GPS does offer several advantages over celestial navigation. For one thing, much greater accuracy, measured literally in single digits of feet. For another, it is continuously updating. Other navigational systems, such as inertial, start with a known fix, and then “drift” after that, with the error in position accumulating over time until the next opportunity to update from a known position.

But as the cited article notes, you can’t jam a sextant. Sorta. Cloud cover actually does a pretty good job of jamming a sextant.

Ordinarily, I’m not at all in favor of gold-plating a system. Here, I’ll make a bit of an exception. While having midshipmen pick up a sextant and the sight reduction tables is the best way to learn, I think it would be pretty silly for the XO or Navigator to stand on the bridge wing shooting Local Apparent Noon with a 100 year old design.

Why not field a modern gyro stabilized star/sun tracker? And of course, an iPad app that you simply input the sightings into. Heck, you could have that capability built into the star tracker.

This is not some fantastic idea I just came up with. Did you know some early ballistic missiles used celestial navigation, with automatic trackers? Day or night, once the missile got up high enough above any clouds and most of the atmosphere, the needed stars were always visible.

The Navy (and the Army to a certain extent) desperately needs to relearn how to operate in an Emission Controlled (EMCON) environment. That means not only using EMCON to deny the enemy information, but also retaining the ability to work when networked sensors are denied or degraded. As fast as we are increasing our capability to field better capabilities through networks, you can bet China and others are working to disrupt or exploit those networks.

Just over fifty years ago, the USAF flew a mission for the first time dedicated to suppressing SA-2 Surface to Air Missile sites in North Vietnam. In spite of the US Army having widely deployed a very similar system domestically for years, the Air Force knew little about the best way to accomplish the mission, which came to be known as Wild Weasel, or more properly, Suppression of Enemy Air Defenses, or SEAD. Tactics, techniques and procedures (TTP) would emerge along with new weapons and technology.

The first dedicated weapon for this SEAD mission was the AGM-45 Shrike, a missile derived from the AIM-7 Sparrow with a passive seeker that homed in on the electromagnetic power radiated by a radar set. Hence the term Anti-Radiation Missile, or ARM.

The Shrike had a few issues, however. Most critically, it had a shorter range than the SA-2 it was intended to counter. But it also had another glaring weakness. If the radar it was attacking suddenly stopped transmitting, it had no means to guide to the target, and would miss.

Still, the mission was suppression of enemy air defenses. By forcing radar operators to shut down, even for a short while, that allowed the main strike package to transit and strike its primary target.

Unfortunately, that simply meant the same suppression would have to be undertaken day after day. The later AGM-78 Standard ARM and its replacement, the AGM-88 High Speed ARM, or HARM, attempted to avoid the shutdown defense by integrating a strapdown Inertial Navigation System (INS) that would guide the missile to the last known position of the emitter. Unfortunately, many modern SAM radars, particularly short range systems, and extremely mobile. Nor were early INS systems particularly accurate. The shutdown still meant most radar systems survived attack.

[youtube https://www.youtube.com/watch?v=WUWLajfDOPg]

The frustration of having to repeatedly spend sorties, time, and ordnance on enemy air defenses lead to something of a doctrinal shift, particularly after Desert Storm and the 1999 air campaign over Kosovo. Emphasis shifted from suppression to Destruction of Enemy Air Defenses, or DEAD (usually pronounced “dee-ad” as opposed to “dehd”). While jamming and HARM would be used to suppress radar guided SAMs, the attack would be pressed and launchers, radars, control sites and communications nodes would be attacked with either conventional munitions, or guided weapons such as Laser Guided Bombs (LGBs), the GPS guided Joint Direct Attack Munition (JDAM) or the gliding GPS guided Joint Stand Off Weapon (JSOW).

The improvements in guidance technologies led the US Navy to reexamine the state of the art in ARMs.This became the Advanced Anti Radiation Guided Missile program, or AARGM. Money for an entirely new ARM wasn’t available, but some funds were, so research began. What they found was that the basic HARM motor and airframe were generally acceptable. The improvements in technology, however, meant that a far more capable seeker system was possible.

What resulted was the AGM-88E HARM. Externally virtually indistinguishable from its predecessors, the AGM-88E uses a much improved passive radar seeker. It also uses a datalink receiver known as Intergrated Broadcast System- Receiver (IBS-R) to receive positional data on threat emitters gathered by Electronic Intelligence (ELINT) platforms such as the EP-3E and RC-135. It also uses a GPS updated INS platform for better guidance. Finally, it has a millimeter wavelength active radar seeker for terminal guidance.

[youtube https://www.youtube.com/watch?v=FCBs1IEk9Fc]

[youtube https://www.youtube.com/watch?v=Id8DEiaKgvQ]

AARGM is in service with the US Navy and Marines. And having just entered service in 2012, the Navy is now looking at a further upgrade, with an RFI issued recently seeking to increase the missile range, most likely through an improved solid rocket motor. What is interesting is that the RFI also lists as a threshold capability internal carriage on the F-35A/C (due to the lift fan, the F-35B has a slightly different internal weapons bay layout).

Almost as soon as electronics entered warfare, Electronic Countermeasures (ECM) began to appear. For instance, in the Battle of Port Arthur, wireless radio communications lead to jamming.

One of the most dangerous threats facing American troops in Iraq and Afghanistan has been the Improvised Explosive Device, or IED. The vast amounts of explosives available in these countries, such as artillery ammunition, or ammonium nitrate fertilizer mixed with fuel oil, has led to some very creative mines and similar devices used to attack our troops.

Early on, most IEDs were triggered via either a pressure plate or command detonated by wire. US troops quickly learned to spot most of these.* The enemy quickly learned to use a variety of radio frequency remote detonators, ranging from simple devices like the key fob used to unlock your car door, to garage door opener, to cell phones and other systems.

The Army quickly moved to counter these radio frequency (RF) remote detonators. Unfortunately, a quick reaction capability** meant the first generation of jammers were broad band devices designed to simply overwhelm any enemy signal. That had the knock on effect of often overpowering friendly use of the RF spectrum. As the Army and Marines began to grasp that RF controlled devices would almost certainly be a part of any future battlefield, they also began to work with industry to determine exactly what they want in ECM to counter the threat, field devices that could be used at every tactical echelon, require minimum training, space, weight and power, and best defeat the enemy without interfering with our own use of the RF spectrum. It should be noted, back in my day in the 80s and 90s, electronic warfare assets were held by the Military Intelligence battalion organic to each division. Teams might be attached to brigades or lower echelons, but there simply was no organic EW or ECM equipment in the maneuver battalions or their vehicles.

Today, virtually every echelon has their own equipment, be it large to defend an installation, vehicle mounted to protect a column of vehicles, or even manpack jammers to defend dismounted patrols.

Let’s take a look at some of the ECM gear in use today, and discuss some issues with them.

First, some terminology. The Army loves acronyms, and in recent years has even taken to embedding acronyms within acronyms. The series of jammers in use today are collectively referred to as CREW, or Counter Radio-Controlled-Improvised-Explosive-Device (RCIED) Electronic Warfare.

ECM systems might be used to protect entire Forward Operating bases. FOBs are popular targets for Vehicle Borne IED (such as a truck bomb) and while most VBIEDs aren’t radio command detonated, it never hurts to cover that contingency). These semi-fixed installations are beyond the scope our discussion today.

That leaves vehicle mounted and manpack CREW systems. Not every vehicle will mount a CREW system. The range of the system is sufficient that one jammer can cover a fairly good number of vehicles. Secondly, not every vehicle has the power and space to mount one. Further, the costs imposed on adding CREW to certain vehicles, such as M1 tanks, is prohibitive, considering their relative invulnerability to most IEDs already. Having said that, Humvee and MRAP units are commonly well equipped with CREW devices. Probably the most common one in use is the DUKE, or ULQ-35.

[scribd id=270222353 key=key-NANQb3E5b1qHtcdwYWq4 mode=scroll]

Note that DUKE isn’t continuously transmitting, but rather spends its time listening for possible enemy signals, and then automatically jams them, often times with very sophisticated waveforms and techniques. DUKE is a wideband system, and covers virtually the entire tactically significant RF spectrum.

But roadside bombs aren’t the only threat our troops face. Particularly in Afghanistan, dismounted patrols move through areas were RCIEDs are common. Those patrols need protection as well. The standard manpack IED jammer is the Thor III.

[scribd id=270222540 key=key-y3TfQxOdQNMUWlYWXpd8 mode=scroll]

You’ll notice there’s not one, but three manpacks in a Thor III system. Three packs are needed to cover the high, medium, and low bands. Unfortunately, that greatly increases the load of mission equipment a dismounted platoon has to carry.

You’ll also note that the size of the pack means that each troop carrying one has no room to carry his own personal equipment such as food, water, and extra clothing. That means their load has to be spread about the rest of the platoon, further exacerbating the load carrying problem.

The Joint IED Defeat Organization, the DoD’s counter IED office, solicited proposals for a pack that would allow a troop to carry both loads, but cancelled the contract.

Given the burden the system imposes on a platoon, one wonders if any commanders have conducted an operational risk assessment and occasionally decided to leave one or two of the packs behind and cover only the most likely threat band.

The program office for electronic warfare is fielding an array of precision jammers, including some that target the triggers for radio-controlled improvised explosive devices and act as sensors to pinpoint the trigger man’s location. These new devices also extend to squads on foot and forward operating bases the protective bubble for wheeled vehicles.

“This is a significant shift from defense — protect your convoy, let’s just get through the day — to go on the offensive for enemy command and control,” said Mike Ryan, electronic warfare program manager at PEO IEW&S.

The next version of the CREW Duke for vehicles merges electronic warfare and cyberwarfare by conducting “protocol-based attacks,” said Ryan, “where you actually get into the system and displace ones and zeroes to break that communication chain between the trigger and the [radio-controlled] IED receiving those ones and zeroes.” This is part of a technology insertion over the next few years.

Basically, in addition to defeating the detonation of one IED, the technology will begin to defeat the enemy’s network. In addition to simply jamming enemy signals, distributed CREW systems will conduct ongoing Signal Intelligence (SIGINT) collection and Traffic Analysis collection. Each system will either record or retransmit its collection for analysis at higher headquarters, which can use this information to discern the enemy Order of Battle, chain of command, and potentially its capabilities and intentions. One suspects future systems will also be linked to an embedded GPS system capability to provide real time or near real time targeting capability.

We personally suspect that since future generations of tactical radios for friendly voice and data use will use software defined waveforms, they will also embed a jamming and EW/SIGINT capability, meaning that each friendly radio will also serve a CREW mission, thus reducing the number of devices needed at the tactical level, and reducing the physical and power burden on a given unit.

*Most. Not all. But a lot of training went into spotting possible IEDs and tell-tale signs of wires and pressure plates.

** Quick Reaction Capability or QRC means not that it acts quickly on the battlefield, but rather that the government was able to quickly contract with industry to field a capability to the forces. The solution is almost always imperfect, but it is at least there.